Apparatus for and method of replacing cables in multicable lifting devices

ABSTRACT

WOUND TWICE ON THE DRIVING DISC, ONCE UNDER THE ROLLERS OF THE PRESSING ROLLER CHAINS AND ONCE OVER THEM. THE METHOD AND APPARATUS OF THE PRESENT INVENTION ELIMINATE THE NECESSITY OF BRINGING IN THE LARGE SPECIAL WINCH WHICH TEMPORARILY FUNCTIONALLY REPLACES THE DRIVING DISC AND ITS ATTENDANT MECHANISMS. NOT ONLY IS SUCH SPECIAL WINCH EXPENSIVE, BUT ITS USE IS IMPOSSIBLE IN SO-CALLED &#34;BLIND SHAFTS,&#34; THE UPPER ENDS OF WHICH DO NOT EXTEND UPWARDLY TO GROUND LEVEL SO AS TO PERMIT THE INSTALLATION OF THE SPECIAL WINCH AT THE HEAD OF THE SHAFT. APPARATUS FOR AND METHOD OF REPLACING CABLES IN MULTICABLE LIFTING DEVICES, SUCH DEVICES HAVING A LIFTING MACHINE WITH A SINGLE DRIVING DISC. WHEN A CABLE IS TO BE REPLACED IN THE LIFTING DEVICE, A NUMBER OF PRESSING ROLLER CHAINS ARE MOUNTED ON THE MACHINE, THERE BEING ONE ROLLER CHAIN FOR EACH TURN OF CABLE ON THE DRIVING DISC, EACH OF THE PRESSER ROLLER CHAINS OVERLYING ITS RESPECTIVE TURN OF THE CABLE AND PRESSING IT AGAINST THE DRIVING DISC, WHEREBY TO ENSURE AN ABSOLUTE SELF-HOLDING OF THE CABLES DURING THE PULLING OF THE OLD CABLES OUT OF THE PIT AND/OR DURING THE LOWERING OF THE NEW CABLES. THE CABLES ARE

March 13, 191.3 r D. IVANOV 3,720,291

APPARATUS FOR AND METHOD OF REPLACING CABLE IN MULTICABLE LIFTING DEVICES 5 Sheets-Sheet 1 Filed Aug. 27, 1970 FIG. 1 FIG. 2

INVENTOR /v4/v nm/vav ATTORNEY March 13, 1973 o. IVANOV 3,720,291

APPARATUS FOR AND IETHOD OF REPLACING CABLE IN MULTICABLE LIFTING DEVICES 5 Sheets-Sheet 2 Filed Aug. 27, 1970 FIG. 4

FIG. 3

Quww R m .n m 0% N W Mm I. D. IVANOV APPARATUS FOR AND METHOD OF REPLACING CABLE IN MULTICABLE LIFTING DEVICES 5 Sheets-Sheet 3 Filed Aug. 27, 1970 |NvEN roR= /V/IN lv/Mlov' BY m... (9.

ATTORNEY March 13, 1913 I. n. IVANOV 3,720,291

APPARATUS FOR AND ETHOD OF REPLACING CABLE IN MULTICABLE LIFTING DEVICES Filed Aug 27, 1970 5 Sheets-Sheet 4;

FIG. 6

INVENTOR.

ATTORNEY March 13, 1913 1. D. IVANOV 3,720,291

APPARATUS FOR'AND METHOD OF REPLACING CABLE IN MULTICABLE LIFTING DEVICES Filed Aug. 27, 1970 5 Sheets-Sheet a,

INVENTOR 2 IVA/V /V4/VOV ATTORNEY Int. Cl. B66b 11/04 US. Cl. 187-20 2 Claims ABSTRACT OF THE DISCLOSURE Apparatus for and method of replacing cables in multicable lifting devices, such devices having a lifting machine with a single driving disc. When a cable is to be replaced in the lifting device, a number of pressing roller chains are mounted on the machine, there being one roller chain for each turn of cable on the driving disc, each of the pressing roller chains overlying its respective turn of the cable and pressing it against the driving disc, whereby to ensure an absolute self-holding of the cables during the pulling of the old cables out of the pit and/or during the lowering of the new cables. The cables are wound twice on the driving disc, once under the rollers of the pressing roller chains and once over them. The method and apparatus of the present invention eliminate the necessity of bringing in the large special winch which temporarily functionally replaces the driving disc and its attendant mechanisms. Not only is such special winch expensive, but its use is impossible in so-called blind shafts, the upper ends of which do not extend upwardly to ground level so as to permit the installation of the special winch at the head of the shaft.

This application is a continuation-in-part of application Ser. No. 739,080, filed June 21, 1968, and now abandoned.

BACKGROUND OF THE INVENTION The pulling out of the worn out carrying and balancing cables in modern multicable lifting devices and their replacement with new ones is a very hard and timeconsuming job. For this purpose separate mobile machines with two friction drums are used now.

A known friction machine of this kind consists of two drums which are driven with equal speed in the one or the other direction depending on whether old cables are pulled out or new ones are lowered by means of the machine. When passing the cables through the machine, each of them is wound several times around the periphery of the two drums. In this way the frictional force between the cables and the driving discs depends on the angle of Winding of the cable on the drum and on the presence of a certain tensile force. The number of windings of each cable around the drums cannot be less than four.

In another known friction machine with two drums for the same purpose, a certain improvement has been introduced. On the first two windings of each cable passing over the drums a certain pressure is exerted in the radial direction by means of pressing roller chains. In this case the force of the friction depends not only on the winding angle of the cables on the drum but also on the magnitude of the tensile force created by the pressing roller chains, owing to which the cable always holds itself on the peripheries of the driving drums of the machine. The number of the windings of each cable on the driving drums of this machine cannot be less than four, as well.

The common shortcoming of the mentioned known friction machines for the replacement of cables in multicable lifting devices is that it is necessary continuously United States Patent O 3,720,291 Patented Mar. 13, 1973 ice to control and keep at a determined value the holding force, i.e., the friction force, by means of a number of controlling-measuring and registering apparatuses.

Another shortcoming of these machines is that owing to the large number of windings of every cable on the drums not more than four cables can be removed or replaced simultaneously.

A shortcoming of these machines is also that the passing of the cables over the peripheries of the drums takes place along a spiral line owing to which the flat balancing cables are subjected to most undesirable overstretching and even deformation of the edges which badly affects the smooth exploitation of the lifting device supplied with such a deformed cable. For the same reason not more than one fiat balancing cable can be replaced at one time.

In order to avoid the above-listed shortcomings of the known friction machines for the replacement of the cables of multicable lifting devices, a new self-holding friction machine with two drums has been proposed wherein both drums are supplied with pressing roller chains and the cables are passed once under the rollers of the pressing roller chains 'and a second time over them with the object of ensuring an absolute self-holding of the cables against skidding over the driving drums. One such friction machine is shown in applicants Austrian Pat. No. 249,925, dated Oct. 10, 1966.

The use of a special machine for the replacement of the cables of multicable lifting devices, however, is not economically advantageous because of the required investment for this special machine which is comparatively little used, for the building of concrete foundations for the machine at each lift pit, for special mains for supplying energy to the powerful electric motors, and also for the transportation of the machine from one pit to the other.

SUMMARY OF THE INVENTION The use of the driving disc itself of the lifting machine of a multicable lifting machine for the replacement of the cables, with little expense for its adaptation for the purpose offers a number of advantages: No expenditure is required for a special machine, for building foundations, for s ecial electric installations, etc.

Thus, it is a primary object of the present invention to provide a method which enables the driving disc which is normally used during operation of the machine to be used also in connection with the replacement of cables.

Furthermore, it is an object of the present invention to provide a method which will enable the replacement of cables to be carried out with the driving disc, which is in any event present, in a simple, expeditious, highly convenient, as Well as inexpensive manner.

The method of using the driving disc of the lifting machine, according to the invention, consists of pressing the cables on the periphery of the disc by a number of pressing roller chains corresponding to the number of the cables, wherein in order to ensure an absolute self-holding of the cables during the pulling out of the old cables from the pit or during the lowering of the new cables down the cable are wound twice on the driving disconce under the rollers of the pressing chains and a second time over them.

In order to realize the double winding of the cables on the periphery of the driving disc-under and over the pressing roller chains-one complete group of diverting rollers is supplied, consisting of as many roller chains as the number of the cables.

BRIEF DESCRIPTION OF THE DRAWINGS The invention has been explained in greater detail with the assistance of the drawings attached, where:

FIG. 1 is a schematic view of a lifting machine having a driving disc, the lifting machine being shown in normal operation;

FIG. 2 is a diagram of the adaptation of the driving disc of a lifting machine, on the site, when pulling out a carrying cable;

FIG. 3 is the same as FIG. 2 but when lowering a new carrying cable;

FIG. 4 is a diagram showing an apparatus for and a method of pulling out of the old balancing cable and lowering a new one;

FIG. 5 is a diagram of an embodiment of a lifting machine having a driving disc set up over a pit tower;

FIG. 6 is a diagram of another embodiment of a lifting machine having a driving disc set up over a pit; and

FIG. 7 is a view in radial axial section through the apparatus of FIG. 6, the section being taken along line 77 of FIG. 6.

DESCRIPTION OF PREFERRED EMBODIMENTS OF THE APPARATUS AND METHOD In FIG. 1 there is schematically shown a lifting machine having a driving disc, the lifting machine being shown in normal operation. The disc which drives both the lifting cable 4 and the balancing cable 7 for the lifting device is designated 1; such disc is driven by conventional driving mechanism, not shown. As shown, the cables 4 and 7 pass upwardly through a pit or shaft 3 in the earth, through a tower 2 erected over the pit, and over respective guiding pulleys 4 and 9 supported on the tower in their travel to and from the driving disc 1. The lifting cable 4 is attached to the top of a lifting cab 6, and the balancing cable 7 extends from the bottom of the cab 6 upwardly along the pit or shaft 3 to the pulley 9. A balancing weight 8 secured to the cable 7 at an appropriate location along its length. When the lifting disc 1 of FIG. 2 is driven in a clockwise direction, the cab 6 rises and the weight 8 falls; when the disc 1 is driven in the reverse direction, the cab 6 is lowered and the weight 8 is pulled upwardly.

FIG. 2 is a diagram showing the driving disc of the lifting mechanism of the device shown adapted, on the site, for the pulling out of a carrying or lifting cable 4. The cab 6 is shown as having been lowered so that the balancing weight 8 has risen at least slightly above a platform-supporting means 12 supported across the tower 2. Thereupon a plate-like support 14 is introduced below the weight so as to rest upon the platform support 12. The portion of the balancing cable 7 above the weight 8 will then have been disconnected. The thus-removed portion of the balancing cable 7 above the weight 8 may be wound upon the same spool, designated 15 in this instance, on which the new cables were wound before their lowering into the pit or shaft 3.

A plurality of roller chains 18, which are shown in more detail in FIGS. 6 and 7, are now brought in and installed at the lifting disc 1, there being one such roller chain 18 for each of the cables 4 extending about the lifting disc 1. Cable diverting rollers 16 and 17 are also mounted as shown in FIG. 2, as well as a plurality of spools, of which one is shown at 15, upon which new cables are wound. The old cable to be removed travels, as before, upwardly along the pit 3 to the supporting and diverting pulley 7, and thence to the driving disc 1. The roller chain 18, the guiding pulleys 16 and 17, and the supply reel 15 are so disposed that the cable 4 first passes about the exterior of the roller chain 18, proceeds to the roller guide 17, and then is reversed to travel between the driving disc 1 and the rollers of the roller chain 18. Upon leaving the driving disc 1, the cable 4 travels to the guiding pulley or roller 16 and thence to the winding spool 15. As above-noted, with the exception of driving disc 1, which engages all of the cables 4, there are separate mechanisms for each of the cables 4, that is, separate roller chains 18, drums or pulleys 16 and 17 and spool 15.

FIG. 3 shows the mechanism shown in FIG. 2 engaged in the replacement of the cable '4 by a new cable. The cab 6 has been pulled up until it is in a position to be supported upon the platform 14 disposed upon the platform supports 12. The former cable 4 has been disconnected from the top of the cab 6 and has been fully wound up upon the reel 15. Thereupon the new cable, likewise shown wound upon the reel 15 is unwound therefrom and brought first over the guide roller 16, then into engagement with the driving disc 1, is removed from the disc 1 by the idle roller 17 to be returned along the outside of the roller chain 18, and finally is directed over the guide pulley 4 and downwardly so that its leading end may be attached to the top of the cab 6.

In these operations, as will be more readily apparent upon the consideration of FIGS. 6 and 7, the tension in the outer turn of the cable 4 which overlies the rollers of the roller chain 18 very forcibly presses the rollers of the roller chain against the inner partial turn of the cable 4 which lies between the rollers and the driving disc 1. All slippage of the cable 4 upon the disc 1 is thereby eliminated. As shown, a platform 10 may be provided across the mouth of the pit 3 to a support cable clamp 11. In FIG. 3, the clamp 11 is shown operatively engaging the balancing cable 7 beneath the balancing weight 8, thereby relieving the platform 14 and its supports 12 from a large part of the weight of the balancing cable.

In FIG. 4, there is somewhat schematically shown an apparatus for and a method of pulling out an old balancing cable and lowering a new one. The cable clamp 11 is here shown as operatively engaging the lifting cable 4, thereby supporting the cab 6 and the lifting cable, even though the other end thereof has been disengaged from operative engagement with the lifting disc 1. The counterweight 8 has been elevated to the position shown, where it is supported on the platform 14. The balancing cable 7 has been disconnected from the lower end of the weight 8 and has been diverted by running over an idle roller 19 and thence to another, upper guide roller 21. From the roller 21 the balancing cable 7, in a balancing cableremoving operation, passes around the exterior of the rollers of the roller presser chain 18, thence to the guiding roller 17, back to the disc 1 this time in contact with the disc and between it and the rollers of the roller chain 18, and then to the guide roller 16 and finally to a take-up spool 20. When a new balancing cable 7 is to be introduced into the apparatus, the cable proceeds from the supply spool 20 and through the above-described path in the reverse direction until it is lowered past the guiding roller 19 into the pit or shaft 3.

In FIG. 5 there is shown an installation wherein the lifting disc 1 is disposed above a tower 2', rather than being located at one side of the tower as in the previously described embodiments. A lifting cable 4b rises vertically within the pit 3 and upwardly through the tower 2' to the exterior of a preser roller chain 18'. The cable 4b then travels around a diverting roller 24 and thence back to the outside of the presser roller chain 18, downwardly partially about a diverting roller 25 and thence to a takeup spool 20'. The heavy line 4b shows the path of the lifting cable when it is being removed from the mechanism or replaced therein. The light line 4a shows the normal path of the lifting cable wherein it proceeds upwardly into direct engagement with the lifting disc 1, the presser roller chain 18' having been removed when the lifting mechanism is restored to such normal operation. A balancing cable 7' proceeds from the surface of the lifting disc 1', downward partially about a large diverting roller 22 and thence into a vertical span extending downwardly into the pit 3.

In FIGS. 6 and 7 a lifting disc 1 and a presser roller chain 18 are shown in detail, such elements being shown in a lifting mechanism disposed immediately above a vertical pit or shaft. As shown in FIG. 6, no tower is here employed, a lifting disc 1 being located immediately above the mouth of the pit 3a; such installation may be employed to advantage, for example, in blind mine pits or shafts, the mouths of which are not accessible to the outside. In the embodiment shown, the lifting disc 1 is depicted as being rotated counterclockwise so as to remove the cable 4 from the pit. The cable 4 travels upwardly, first engages the driving disc and is pressed thereagainst by inner faces of the rollers 26 on the presser roller chain, the cable 4 then travelling downwardly and partially around an idle diverting roller 32 which is journalled upon a supporting rack 34. The cable then travels upwardly and around the outside of the presser roller chain and then travels vertically downwardly to pass partially about a fixed located idle roller 35, the cable then passing to the right to be taken out upon a winding spool (not shown).

In FIG. 7 there is shown a portion of the driving disc 1 at the location of a single lifting cable 4; it will be understood that the structure shown in FIG. 7 is repeated, axially of the lifting disc 1, for as many cables 4 as there are employed in the lifting mechanism. In the portion of the disc 1 shown, there is employed a facing ring 29 made of hard, durable material, the ring 29 being provided with a part circular groove thereabout to receive the cable 4. The presser roller chain 18 is composed of a plurality of rollers 26, each of which is journalled upon its individual transverse axle 28. Successive axles 28 are connected by pairs of links, the links of the inner set being designated 27' and of the outer set 27 in FIG. 7. The rollers 26 are provided with part circular annular grooves 31 which receive the cable 4. It will be apparent that the inner turn of the cable 4 is forcibly pressed between the lower or radially inner face of each of the rollers 26 and the groove 30 in the lifting disc 1, that the outer run of the cable 4 is received within the annular groove 31 in the radially outer part of each of the rollers 26, and that the tension in such outer turn of the cable 4 thrusts the lower or inner turn of the cable into forcible, non-slipping contact with the portion 21 of the lifting disc 1.

Although the invention is illustrated and described with reference to a plurality of preferred embodiments thereof, it is to be expressly understood that it is in no way limited to the disclosure of such a plurality of preferred embodiments, but is capable of numerous modifications Within the scope of the appended claims.

What is claimed is:

1. Apparatus for replacing a cable of a lifting device employing a plurality of cables, comprising a cable-driving means having only one driving disc permanently installed at and forming a part of said lifting device, the lifting device having a vertical shaft into which the cables normally extend, the vertical shaft having a blind upper end, comprising means for pressing against and locating adjacent the periphery of the driving disc at the location of each cable a plurality of pressing rollers disposed as a chain, means for guiding each of the cables along the exterior of said pressing rollers at a side thereof directed away from the driving disc, the transfer roll guide to which the cable then travels, and means for guiding the cable to the interior of the pressing rollers of the respective chain between the latter and the driving disc so that each cable has two windings, one on the driving disc and the other on the outside of the respective pressing rollers around the driving disc, to ensure self-holding of the cable, one of the spans leading to and from the transfer roll guide leading to said one winding and the other of said spans leading to the other of said windings, the driving disc being the only source of driving tension other than gravity applied to the cables.

2. In a method of replacing a cable of a lifting device employing a plurality of cables passing about and driven only by a single driving disc permanently installed at and forming a part of said lifting device, the lifting device having a vertical shaft into which the cable normally extends, the vertical shaft having a blind upper end, comprising the steps of pressing against and locating adjacent the periphery of the driving disc at the location of each cable a plurality of pressing rollers disposed as a chain, and guiding each cable along the exterior of said pressing rollers at a side thereof directed away from the driving disc, to a transfer roll guide, and to the interior of the pressing rollers of the respective chain between the latter and the driving disc so that each cable has two windings, one on the driving disc and the other on the outside of the respective pressing rollers around the driving disc, to assure self-holding of the cable, one of the spans of cable leading to and from the transfer roll guide leading to said one winding and the other of said spans leading to the other of said windings, the driving disc being the only source of driving tension other than gravity supplied to the cables, driving the single driving disc in such direction as to remove the cables from the shaft and from around the driving disc and the chains of pressing rollers, and replacing the cables by new cables by presenting said new cables to the single driving disc, the transfer roll guide, and the chains of pressing rollers in the same manner as defined above in connection with the cables which were removed, and driving the single driving disc in the reverse direction, whereby to feed the new cables in directions opposite from those in which the old cables moved when being removed, whereby to install the cables about the lifting disc and in the vertical shaft, and thereafter removing the chains of pressing rollers from the single driving disc.

References Cited 249,925 10/ 1966 Austria 254-175.7

HARVEY C. HORNSBY, Primary Examiner US. Cl. X.R. 254-] 

